1. Field of the Invention
This invention pertains to exercising apparatus, and more particularly to machines for developing arm strength.
2. Description of the Prior Art
Various types of equipment have been developed to assist persons strengthen their muscles. For example, machines for developing arm muscles are well known and in widespread use. U.S. Pat. Nos. 3,042,023; 4,239,210; and 5,256,125 show machines that are useful for developing a person's biceps.
Arm muscles in addition to biceps are important in the sport of arm wrestling. In that sport, the competitors' elbows are placed side-by-side on a horizontal surface with the forearms vertical. Each person attempts to pivot his arm at the elbow across the front of his torso. To pivot his arm, he must overcome the resisting force exerted by the other contestant.
To develop the muscles used in arm wrestling, a person can lift a weight as he pivots his arm. U.S. Pat. Nos. 3,019,019 and Des. 264,236 disclose suitable weight lifting apparatus. U.S. Pat. Nos. 4,634,115 and 5,458,554 show machines in which springs provide the resistance to arm pivoting.
A disadvantage of the prior weight and spring related machines is that the resisting forces can be adjusted only in course increments. Further, the resisting forces of the machines of the U.S. Pat. Nos. Des. 264,236; 4,634,115; and 5,458,554 are not uniform over the range of arm motion.
Thus, a need exists for improvements in arm wrestling exercise machines.